Five centuries after the arrival of Columbus, one of the last battles in Europe’s conquest of the New World is being fought in the scorched heart of South America.

In the semi-arid forests of the Chaco region of Paraguay, where summer temperatures top 40C (104F), the continent’s last uncontacted Indians outside of the Amazon basin are on the run, their traditional forest home increasingly encroached upon by ranchers.

Today there are said to be only four small bands of Totobiegosode, who have had no contact with the world beyond.

Outside pressure has already forced three other bands of the tribe come out of the forest since 1979. These formerly nomadic tribespeople struggle to maintain a semblance of their traditional way of life in camps on the edge of the agricultural colonies that invaded their territory.

The last group emerged from the forests in 2004 and its leader, Poai Picanerai, is in no doubt about whom to blame. “Before, things were good when we were in the forest,” he said. “But we could not stay there because the whites have cut everything. The whites are violent. They just want land. We are afraid of them, they are very aggressive.”

He has relatives among the last bands still in the wilderness and knows that they are afraid, constantly on the run from workers employed by ranchers to clear the forest and with it the Totobiegosode’s historical and sacred sites.

“They are afraid of the whites. But now they are also afraid of us who have left the forest because we now wear clothes and those in the forest do not,” Mr Picanerai added.

The increasing demand for land in eastern Paraguay and south-central Brazil on which to grow soya beans for export to Asia and Europe, means that the ranchers are now looking to Chaco, one of South America’s last frontier regions, as a prime breeding ground for their cattle. But the Totobiegosode say that this is their territory. “We want the whites removed and our territory left to us so those in the forest can be left in peace,” their leader said.

The tribe laid claim in 1993 to an area of 550,000 hectares (1.36 million acres) that they say is theirs, although it is only part of their traditional territory. After 15 years they have received title to only 100,000 hectares. Now the Totobiegosode and other Chaco peoples are instructed by signs on farmland not to hunt on their traditional lands, lest they upset grazing cattle. As in many such situations over the centuries, the Totobiegosode did not posses legal title to land that they had inhabited for centuries and this has been used by Europeans and their descendants to justify its seizure and conversion into farmland.

Opponents of the Totobiegosode claim say that it is European anthropologists and not the tribe who are behind the demand for their land to be returned. “They want out of the forest,” claims a missionary from the controversial New Tribes Mission group, which works to convert the Totobiegosode to Christianity. “They are not as interested as anthropologists would like them to be in spending their days hunting.” The missionary would not give his name.

Others say that the land claim is too great for such a small group that produces very little.

“The prejudice here is to say to indigenous groups, ‘You do nothing, you do not need so much land’. Locals say we are crazy demanding so much land for so few Totobiegosode but there are 50 family groups making the claim on lands that today are owned by just 16 landlords,” says Verena Regehr, a Swiss anthropologist and founder of Gente, Ambiente y Territorio (People, Environment and Territory), which works to defend the rights of the Totobiegosode.

Anthropologists are in no doubt about what will happen if the ranchers seize the Totobiegosode’s land. “They are being forced to live in an ever smaller patch of forest and in 20 to 30 years there will be little left and no way for them to continue their way of life,” says Jonathan Mazower, campaigns co-ordinator for Survival International, which presses for the rights of indigenous peoples.

For Mr Picanerai, the struggle for the forest is the struggle for his people’s future: “We were much more before contact with the whites. Many died of sickness when we entered the colonies. Because they are destroying the environment it affects everything.”

Land that time forgot

— The Chaco is a semi-arid region covering the eastern two thirds of Paraguay, as well as parts of Bolivia, Argentina and Brazil

— Jesuit missionaries were the first Europeans to make contact with the tribes there in the 16th century

— Paraguay fought a bloody war with Bolivia — satirised by Hergé in Tintin and the Broken Ear — for control of the region in the 1930s

— Mennonite settlers from Europe began farming cattle in the Chaco in the 1920s. When the locals resisted, the pacifist Mennonites called in the Paraguayan Army

— As late as the 1950s soldiers could be freed from military service in return for the head of an Indian

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